There's a fascinating tension with anti-aging drugs, which is that your preference would obviously be to take them as early as possible, so you spend more time at a younger age as opposed to just prolonging the last years of your life, where you'll be stuck in a nursing home anyway. But taking experimental drugs while you're young is also much higher risk, and you might see people sacrificing their 20s for the sake o…
Taurine and Vitamin E are readily available and seem prudent. For melatonin, tryptophan plus niacin would maximize the serotonin pathway (note this is dangerous when used with SSRIs). How many of these are easily available? I had no idea that royal jelly is sold as a supplement.
It is also likely the most easy to study, as we have 60-70 years of usage that is not correlated with prevalence of other diseases that might skew life expectancy (like metformin etc.), and quite high-quality medical records by virtue of it being vended on a prescription basis.
Despite this, there is not really any clear evidence that it increases life expectancy.